Presser-foot-lifting mechanism for sewing-machines.



J. HEGGIE. PRESSEK FOOT LIPTING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MB. 9 1909.

998,845, v Patented July 25, 1911.

COLUMBIA PLANOGRAPH (10.. wAsHINumN. D. c.

Uhllt El) S JAMES I-IEGGIE, OF CLYDEBANK, SCOTLAND, ASSIGNOR TO THESINGERJVIANUFAC- TUBING COMPANY, OF ELIZABETH, NE'l/V JERSEY.

PRESSER-FOOT-LIFTING MECHANISM FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented July 25, 1911.

Application filed February 9, 1909. Serial No. 476,956.

To all whom it may concern:

Be it known that I, Juries l-lnoern, a subject of the King of the UnitedKingdom of Great Britain and Ireland, and residing at Clydebank,Dumbartonshire, Scotland, have invented a certain new and usefulImprovement in Presser-Foot-Lifting Mechanism for Sowing-Machines, ofwhich the following is a specification.

This invention relates to sewing machines for use in stitching leather,saddlery and like goods of uneven thickness, in which the feeding of thework is effected by a feed dog below acting in conjunction with avibrating or feeding presser above the work: and it has for its objectto provide a simplified and improved arrangement or combination ofmechanism for so actuating the presser that it automatically climbs thestopped or uneven surface of the work as the thickness of the latterincreases and in like manner descends as the thickness decreases, whilethe extent of lift over the goods remains practically uniform throughoutand undue pressure or thud on the de scent of the presser is avoided.

In the accompanying drawings Figure 1 is a front view of the head of asewing machine embodying the invention, the face plate being removed,Fig. 2 is a part plan thereof, and Fig. 3 is a part vertical section onthe line 33, Fig. 2.

Referring to the drawings, the lifting movements of the presser areeffected by a cam A formed on or fitted to the usual crank disk 0 on theforward end of the needle bar actuating shaft B. The needle-bar Z),carrying the needle 11, derives its usual reciprocatory movements fromthe actuating shaft B through the pitman (Z connected with thescrew-stud 0 carried by the crankdisk 4. The said cam is tracked byroller 0 carried by a forked portion 0 at the lower end of a verticalplunger G fitted in the machine head D adjacent the face plate, (notshown). The plunger is slotted at its upper end 0 and the slot isentered by the end of a short clamping lever E pivoted at E on a jawedsleeve G fitted loosely on the upper end of the presser bar H so thatthe latter may freely slide within the sleeve G which is held inposition by a screw threaded stud h entering the end of the presser bar,a washer I and spring J being interposed.

Between the aws of the sleeve G is a clamp ing member or collar Kthrough which the presser bar passes freely when no pressure is appliedto the clamping collar but which presser bar is rigidly held by thecollar K when the end of the pivoted clamping lever E or, as shown, thepoint of an adjust;- able set pin or contact screw L carried thereby, isbrought to bear on the side of the collar K so as to cause it to engagethe presser bar H. As shown :in the drawings, the sleeve G is forked toform the two spaced jaws which are perforated to fit the presserbar Ifand the clan'iping member or collar K is also perforated to loosely fitthe pres -1er-bar upon which it is locked between and by means of thespaced aws of the collar G in the desired relation to the other membersof the lifting mechanism. As the collar K embraces the presser bar H andengages such part of its length as is within it for the time being, thecam A imparts a lift of uniform extent to the presser from its positionof rest on the surface of the work irrespective of the thickness of thelatter, while on the descent of the plunger C when cleared by the cam Athe presser bar H is released from the collar so that the presser dropsto rest on the work. Thus, while the presser climbs upward on to astepped surface or downward therefrom, the lift remains normal and thethud due to excessive lift and drop of the presser is avoided.

Having now described my invention what I claim and desire to secure byLetters Patent of the United States is 1. In a sewing machine, thecombination with the needle-bar actuating shaft, a reciprocatingneedle-bar, an operative connection between the forward end of saidshaft and the needlebar, and a presser-bar, of a sleeve forked andperforated to form two spaced jaws fitted upon and embracing saidpresser-bar, a clamping member perforated to fit said presserbar andlocked thereon be tween the jaws of said sleeve, a lever piv oted tosaid sleeve, a reciprocating plunger adapted on its movement in onedirection to move said lever on its pivot and thereby bring the clampingmember into clamping engagement with the presser-bar, and a cam on theneedle-bar actuating shaft adjacent the connection with the needle-barfor opcrating the plunger.

2. In a sewing machine, the combination with the needle-bar actuatingshaft, a reciprocating needle-bar an operative connection between saidshaft and the needle-bar, and a presser-bar of a jawed sleeve embracingsaid presser-bar, a clamping collar loosely fitted upon the presser-barand locked between the jaws of said sleeve, a lever pivoted to saidsleeve and provided with a contact pin whose point is adjustable towardand from said collar, a reciprocating plunger mounted for movementparallel with the presser-bar and adapted on its movement in onedirection to move said le ver on its pivot and thereby bring said collarinto engagement with the presserbar, and a cam on the needle-baractuating shaft adjacent the connection with the needle-bar foroperating the plunger.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JAMES HEGG-IE.

Vitnesses VVALLAGE CRANSTON F AIRWEATHER, lVALLAoE FAIRVEATHER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

